This proposed study represents an extension of the Yale Epidemiologic Catchment Area (ECA) Project with the transition in funding from a cooperative agreement to a RO1 grant. The ECA is a large scale multisite epidemiologic community survey of psychiatric disorders in five US communities: New Haven, Eastern Baltimore, St. Louis, Piedmont, and Los Angeles. Information on the rates, correlates, and course of psychiatric disorders and treatment utilization on over 15,000 persons living in the community and in institutions has been collected. Considerable progress has been made in the methodology for collecting and managing data and in conducting basic analysis of the data available. Because of the sequence in which the ECA sites were funded, cross-sectional and longitudinal data from all five ECA sites and all waves will be available to us for the first time for analysis by January, 1986 when our current funding ends. We are now requesting two years of funding in order to extend our epidemiologic analysis of data to include data from all five sites and all waves. This proposal focuses on analyses in two areas where the investigators have considerable expertise and active research programs. Our aim is to use both the cross-sectional and the longitudinal epidemiologic data from all five sites to: (1) understand the epidemiology of the affective disorders, their subtypes, their subclinical manifestations and their overlap with other disorders particularly anxiety disorders, and (2) conduct analyses of mental health related treatment taking into account subclinical cases and determining the extent to which there is differential utilization by specific subpopulations.